SMA blade twist system: from the requirements to the demonstration in relevant environment

In the present work, an overview is provided on the activities performed by CIRA, DLR and Univ of Bristol to develop and test a morphing system aimed at altering the twist of a blade to enhance the performance of the main rotor. The activities were performed within the research Project of “Shape Adaptive Blades for Rotorcraft Efficiency” (SABRE, H2020, 2017-2021), a Consortium constituted by six Partners (Univ. of Bristol – leader, Univs. of Munich, Delft and Swansea and the research centers of DLR and CIRA). Moving from the original features of the blade and the requirements of the reference rotorcraft, a layout of the architecture was sketched. A refined numerical model was then implemented to accurately predict the functionality of the concept and verify its safety compliance with the test facilities it was conceived for. Laboratory tests were thus performed on a dedicated prototype. Finally, on this basis, two other demonstrators were built and finally tested in the just mentioned wind tunnel and whirl tower plants